Operation CHARM: Car repair manuals for everyone.

ABS-212

F. ABS-211, ABS-212 Wheel sensor signal

ABS-211 Wheel sensor signal LH front wheel, wheel speed incorrect
ABS-212 Wheel sensor signal RH front wheel, wheel speed incorrect

FA. DTC information

Substitute value

If the control module registers that there is no wheel sensor signal when driving is started from a speed under 6 km/h (4 mph) or if the slowest wheel rotates more than 40-60% (depending on the speed of the vehicle) of the fastest wheel but the wheel sensor circuit is still unbroken, fault code ABS-211 or ABS-212, depending on the wheel sensor.

Substitute value

- ABS/TRACS outs out.
- EBD system is available.

Possible source

- Loose wheel sensor
- Defective wheel sensor
- Defective pulse wheel
- Wheel locking when driving
- Contact resistance in the connections

Fault symptom(s)

- If the ABS function cuts out,there is a risk of the wheels locking when braking.
- In cars with TRACS, the anti-wheel slip system cuts out.

Caution! If the fault becomes intermittent, the ABS warning indicator will only go out once the speed exceeds 20 km/h (12.5 mph) in the next driving cycle.

Fault-tracing begins with FB. Other DTCs, status notifications and status checks.

FB. Other DTCs, status notifications and status checks

[FB1]

Status notification






Is a permanent fault registered ?

Yes: FB2
No: Fault-trace as per FD. Incorrect wheel speed. Intermittent fault.

Other DTCs

- Note other DTCs









Select one of the above alternatives to continue

Alternative 1: Fault-trace as per FC. Incorrect wheel speed. Permanent fault.
Alternative 2: FB3

[FB3]

ABS-211 or ABS-212, and ABS-311 or ABS-312 (for the same wheel)

Fault-trace as per JC. Circuit fault. Permanent fault. ABS-311

Then continue with: FB4

[FB4]

Status check






- Ignition on
- Go into rolling value, list 1

Note the wheel speeds
Test drive the vehicle. Maintain an even speed without turning

Warning! The ABS and EBD systems are not available while Volvo Diagnostics is activated. Take great care when test driving as there is a serious risk of wheel locking when braking

Check that the wheel in question has the same speed as the other wheels
Has the wheel in question the same speed as the other wheels ?

Yes: Fault-trace as per FD. Incorrect wheel speed. Intermittent fault.
No: Fault-trace as per FC. Incorrect wheel speed. Permanent fault.

FC. Incorrect wheel speed. Permanent fault

[FC1]

Connect the test box and check the contacts

DDDD. Brake fluid, replacement without bleeding unit. Refer to Hydraulic System - Brake Fluid - Service and Repair - Procedures Service and Repair

Then proceed to: FC2

[FC2]

Check the resistance in the wheel sensor circuit






- Ignition off
- Control module disconnected

Connect an ohmmeter between test box:
#4 and #11 (DTC ABS-211).
#3 and #18 (DTC ABS-212).

The ohmmeter should indicate 1040-1160 ohms.

If reading Is OK: FC6
If reading is incorrect: FC3

[FC3]

Check for resistance in the wheel sensor






- Ignition off
- Remove the wheel for better access
- Clean the wheel sensor contact. Brush and blow clean
- Disconnect the wheel sensor

Connect an ohmmeter between wheel sensor contact connections 1 and 2.
The ohmmeter should indicate 1040-1160 ohms.

If reading is OK: FC4
If reading is incorrect: FC5

[FC4]

Check for contact resistance and oxidation

The DTC has been caused by poor contact in the wheel sensor contact

Check the wheel sensor contact for contact resistance and oxidation and take appropriate action as per [IIIB5]. Check Communication to Control Module [III]

Then continue with: FC18

[FC5]

Replace a component

Test with a new wheel sensor as per KKKKA. Front wheel sensor, replacement. Refer to Sensors and Switches - Brakes and Traction Control - Wheel Speed Sensor - Service and Repair - Procedures Service and Repair

Then continue with: FC16

[FC6]

Check the signal leads






- Ignition off
- Connect the control module
- Ignition on

Connect a voltmeter between the test box:
#8 and #4 (DTC ABS-211).
#8 and #3 (DTC ABS-212).

The voltmeter should indicate 2.3V.

If reading is OK: FC9
If value is lower: FC7
If value is higher: FC8

[FC7]

Check for short circuiting









Check the cable between wheel sensor contact connection:
2 and control module #4 (DTC ABS-211)
1 and control module #11 (DTC ABS-211)
2 and control module #3 (DTC ABS-212)
1 and control module #18 (DTC ABS-212)
for short circuiting to ground as per [IIIB3]. Check Communication to Control Module [III]

Then continue with: FC18

[FC8]

Check for short circuiting









Check the cable between wheel sensor contact connection:
2 and control module #4 (DTC ABS-211)
1 and control module #11 (DTC ABS-211)
2 and control module #3 (DTC ABS-212)
1 and control module #18 (DTC ABS-212)
for short circuiting to power as per [IIIB4]. Check Communication to Control Module [III]

Then continue with: FC18

[FC9]

Check the wheel bearings






Check that the wheel bearing of the actual wheel is not seized
Is the wheel bearing OK?

Yes: FC11
No: FC10

[FC10]

Action

Take appropriate action for the wheel bearing. The front wheel bearings are not adjustable

Then continue with: FC18

[FC11]

Check the brakes






Hint: A seized brake can lock one or both wheels when driving. This means that the wheel sensor signal will not be activated

Check that the brake caliper is not seized so that the wheels may lock
Are the brakes OK?

Yes: FC13
No: FC12

[FC12]

Action

Take appropriate action for the brakes

Then continue with: FC18

[FC13]

Check the wheel sensor






- Ignition off

Note! Do not disconnect the wheel sensor

- Remove the wheel for better access

Check that the wheel sensor is positioned close up to the spindle/wheel shaft. There should be no dirt between the sensor and the the contact surfaces
Remove the sensor as per KKKKA. Front wheel sensor, replacement.
Sensors and Switches - Brakes and Traction Control - Wheel Speed Sensor - Service and Repair - Procedures Service and Repair and check that the wheel sensor point is intact
Is the wheel sensor OK ?

Yes: FC15
No: FC14

[FC14]

Take appropriate action and replace the component






A loose wheel sensor is reinstalled as per KKKKA. Front wheel sensor, replacement
A damaged wheel sensor is replaced as per KKKKA. Front wheel sensor, replacement.
Sensors and Switches - Brakes and Traction Control - Wheel Speed Sensor - Service and Repair - Procedures Service and Repair

Then continue with: FC18

[FC15]

Check the pulse wheel

Check that the pulse wheel is positioned securely and is undamaged (all teeth intact) and is not scratched etc.
Is the pulse wheel OK ?

Yes: FC16
No: FC17

[FC16]

Check for contact resistance and oxidation

The DTC has been caused by poor contact in the wheel sensor or control module contacts
Take appropriate action for contact resistance and oxidation to the wheel sensor and control module contacts as per [IIIB5]. Check Communication to Control Module [III]

Then continue with: FC18

[FC17]

Action

Take appropriate action for the pulse wheel

Then continue with: FC18

[FC18]

Verification






Hint: After repair it is necessary to check that the fault has been rectified

- Ignition off
- Reconnect the contacts,components etc.
- Ignition on
- Go into running value, list 1

Note the wheel speeds
Test drive the vehicle.
Maintain an even speed without turning

Warning! The ABS and EBD Systems are not available while Volvo Diagnostics is activated. Take great care when test driving as there is a serious risk of the wheels locking when braking

Check that the wheel in quesion has the same speed as the other wheels
Has the wheel in question the same speed as the other wheels?

Yes: Fault corrected
No: FC19

[FC19]

Fault-tracing information

The verification result shows that the fault persists.
Do you want to exit fault-tracing?

Yes: Fault not corrected
No: FC1

FD. Incorrect wheel speed. Intermittent fault

[FD1]

Check for a locked wheel





A locked wheel when driving can cause the wheel sensor signal to fail which can cause a DTC to be activated
The wheel can be locked by a temporary seizing of a wheel bearing, brake caliper or parking brake.
Driving with the parking brake on can cause a DTC

Then continue with: FD2

[FD2]

Check the wheel sensor and pulse wheel






Check that the wheel sensor is positioned up to the spindle/wheelshaft

Then continue with: FD3

[FD3]

Check the leads and connections






Check the wheel sensor and control module contacts for contact resistance and oxidation as per [IIIB6]. Check Communication to Control Module [III]
Check the cable between wheel sensor contact connection:
2 and control module #4 (DTC ABS-211)
1 and control module #11 (DTC ABS-211)
2 and control module #3 (DTC ABS-212)
1 and control module #18 (DTC ABS-212)
for intermittent breaks as per [IIIB2], intermittent short circuiting to ground as per [IIIB3] and intermittent short circuiting to power as per [IIIB4]. Check Communication to Control Module [III]

Then continue with: FD4

[FD4]

Fault-tracing information

For intermittent faults fault-tracing is not followed by a verification because the fault is not present at this moment.
Do you want to repeat fault-tracing?

Yes: FD1
No: Operation done